Conventionally, there has been known an image forming apparatus configured to keep an amount of slackness of a sheet conveyed through between an image forming unit and a fixing unit within a predetermined range. The image forming apparatus includes a motor configured to generate a driving power for driving a fixing unit, a sensor provided between the image forming unit and the fixing unit and configured to detect an amount of slackness of the sheet and a control unit configured to control a rotating speed of the motor based on a detection result of the sensor and to adjust a conveying speed of the fixing unit.
In order to simplify the entire control of the image forming apparatus, it would be more preferable to configure the image forming apparatus to have a capability to adjust a sheet conveying speed in the fixing unit without controlling the rotating speed of the motor.